Documentation ============= Permutations ------------- The ``grobnercrystals.Perm`` class is a class for permutations which includes useful methods for working with matrix Schubert varieties: .. autoclass:: grobnercrystals.Perm :members: Filtered RSK ------------ Grobnercrystals includes a function for computing filteredRSK of a matrix with respect to a given Levi datum. .. note:: This function takes numpy matrices as input. .. autofunction:: grobnercrystals.filtered_RSK() Crystal Operators on Matrices ----------------------------- .. note:: These functions take numpy matrices as input. .. autofunction:: grobnercrystals.e() .. autofunction:: grobnercrystals.f() Polynomial Rings ---------------- Grobnercrystals includes a class for defining a polynomial ring in an m by n matrix of variables. .. autoclass:: grobnercrystals.PolRing :members: Ideals and Bicrystalline Tests ------------------------------ Ideals are constructed using the ``grobnercrystals.BIdeal`` class. Every ``BIdeal`` is an ideal of a polynomial ring in an m by n matrix of variables, implemented as a ``PolRing`` object. This class has a ``.bicrystalline()`` method for checking whether the ideal is bicrystalline .. note:: The ``.bicrystalline()`` method does *not* check whether the ideal is stable under the given Levi group, only whether the set of its non-standard monomials is closed under all admissible bicrystal operators for that Levi group. See :ref:`group-actions`. .. autoclass:: grobnercrystals.BIdeal :members: Interesting Classes of Ideals ----------------------------- Grobnercrystals provides functions for defining several ideals of interest. .. autofunction:: grobnercrystals.shape_ideal() .. autofunction:: grobnercrystals.classical_det_ideal() .. autofunction:: grobnercrystals.msv() .. autofunction:: grobnercrystals.eff_msv() .. autofunction:: grobnercrystals.mrv() The following function is useful for defining various determinantal ideals. .. autofunction:: grobnercrystals.minors() .. _group-actions: Group Action Checks ------------------- .. autofunction:: grobnercrystals.check_action() Polynomials and Schur Expansions -------------------------------- Grobnercrystals includes a special class ``SplitPoly`` for polynomials in two sets of variables. This class has a ``.expand()`` method for computing split-Schur expansions of such polynomials. .. autoclass:: grobnercrystals.SplitPoly :members: